I am down in Belize. We don't have all that many Hobie Catamarans down here, but it appears that the predrilled holes in the Getaways' tiller crossbars that line up with the pre-drilled holes in the tiller arms prevent the rudders from being parallel with one another - and parallel with the boats' centerlines - when the cross bars and the tiller arms are attached. The rudders actually cant inwards toward one another at almost a 15 degree angle. This creates drag! Is there some reason Hobie thinks this is a good idea? I don't get it. I think the tiller bar should be lengthened a bit so the rudders aren't forced to slant inwards. Your thoughts?

The rudders should be parallel or close to it. Best if Toe-in just a bit, but certainly not 15 degrees. 1/8" to 1/4" toe-in is likely optimum.

If they have aluminum rudder castings, the tiller arms bow inboard and the tiller crossbar is shorter. Mount the rudders on the opposite hulls and connect the tiller crossbar... you get highly Toe-in rudders. This could be the simple answer.

Sure you have a Getway tiller crossbar? The Wave crossbar is shorter and does not have a hiking stick hinge.

Older tiller crossbars that were used on the aluminum castings were shorter. The EZ Loc rudder system uses a longer one.

I highly suspect a miss-matched rudder system / tiller crossbar is the issue.